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Year 2 > Introduction to Endocrinology > Flashcards

Flashcards in Introduction to Endocrinology Deck (43)
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1
Q

Define Endocrinology

A

The study of hormones (and gland of origin), their receptors, intracellular signalling pathways and associated disease

2
Q

Define Paracrine

A

Acts on adjacent cells

3
Q

Define Autocrine

A

Feedback on same cell that secreted hormone

4
Q

What form of Iodotyrosine is most active

A

T3

5
Q

What are thyroid hormones bound to

A

TBG (Thyroid-Binding Globulin)

6
Q

Where are thyroid hormones stored

A

In colloids bound to thyroglobulin

7
Q

How does Dopamine effect the release of prolactin

A

Inhibits the release of prolactin

8
Q

What would happen to prolactin levels if the infundibulum of the pituitary gland was destroyed

A

Prolactin levels would increase

9
Q

Does the anterior pituitary gland have an arterial blood supply

A

Nope

10
Q

Blood supply of the anterior pituitary gland

A

Hypothalamus-hypophyseal portal veins

11
Q

What is the benefit of the hypothalamus-hypophyseal portal veins

A

Provides a mechanism for hormones of the hypothalamus to directly alter the activity of cells of the anterior pituitary gland by bypassing circulation

12
Q

What is the benefit of the hypothalamic-pituitary axis

A

Allows for an amplified response

13
Q

What cells produce FSH and LH

A

Gonadotrophs

14
Q

What cells produce ACTH

A

Corticotrophins

15
Q

What cell secrets TSH

A

Thyrotrophs

16
Q

Where is prolactin produced

A

Lactotrophs

17
Q

Where is GH produced

A

Somatotrophs

F: FSH
L: LH
A: ACTH
T: TSH
P: Prolactin 
I: Ignore
G: GH
18
Q

What does FSH and LH target

A

Gonads

19
Q

What does LH and FSH stimulate together

A

Germ cell development

20
Q

What does FSH exclusively stimulate

A

Release of oestrogen

21
Q

What does the release of oestrogen stimulate

A

Release of LH

22
Q

Role of LH

A

Stimulates the release of the egg which stimulates progesterone release

23
Q

Role of progesterone

A

Results in increased thickening of the uterine wall

24
Q

How does LH effect males

A

On leydig cells - testosterone release

25
Q

How does GH effect an individual

A

Growth and protein synthesis

26
Q

How does GH effect blood glucose levels

A

Increases:

Causes gluconeogenesis
Inhibits Insulin
Lipolysis

27
Q

Role of GH on the liver

A

Increases protein synthesis and stimulates production of IGF-1 which acts on skeletons to increase cartilage proliferation

28
Q

What compound is IGF-1 similar to

A

Insulin

29
Q

Role of IGF-1

A

Basically GH’s servant. It is produced by liver and stimulates body growth in every cell of the body

30
Q

Where is ACTH produced

A

Anterior Pituitary Gland

31
Q

Role of ACTH

A

Stimulates adrenal cortex to secrete cortisol from zona fasiculata , androgens from zona reticular and adrenaline from adrenal medulla

32
Q

Where is dopamine produced

A

Hypothalamus

33
Q

Does a negative feedback loop exist for prolactin

A

No, because of the role of Dopamine

Prolactin acts on the hypothalamus to cause the release of dopamine

34
Q

What happens when GH binds to the hypothalamus

A

GH causes secretion of somatostatin which is inhibitory

35
Q

Where is Vasopressin produced

A

Supraoptic nucleus of the hypothalamus

36
Q

Where is Oxytocin produced

A

Paraventricular body

37
Q

Describe the pathway of from the supraoptic and paraventricular nuclei

A

Moves down the infundibulum and terminates in posterior pituitary gland

38
Q

Where are Vasopressin and oxytocin stored

A

In vesicles and accumulate in axon terminal in the posterior pituitary glands

39
Q

How does ACTH cause fluid retention

A

ACTH causes release of aldosterone which causes up regulation of Na+/K+ pumps (3 Na out for 2K in)

40
Q

Role of Oxytocin in breast milk

A

Needed for ejection of milk by myoepithelial cells

41
Q

Role of oxytocin during pregnancy

A

Stimulates contraction of uterine smooth muscles until baby is born and labour

42
Q

What is the consequence of oxytocin having a short half-life

A

More has to be produced on a minute-by-minute basis

43
Q

What type of receptors do ALL pituitary and hypothalamic hormones act on

A

G-protein couples receptors

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